120/60-17 Contact patch

Discussion in 'Tech' started by Auron, Aug 12, 2019.

  1. Auron

    Auron Well-Known Member

    Say I'm just a casual track day rider that much preferences the turning characteristics of the smaller 120/60 tire. I don't use all of the 120/70 but I do get right to the edge of the 120/60. How does this play into wear and grip given I'm not using the whole 120/70 tire?
  2. Pneumatico Delle Vittorie

    Pneumatico Delle Vittorie Retired "Tire" Guy

    Ok let's start with the facts.
    What bike and year?
    Stock wheels and OE sizes?
    Which tire and model of said tire F &R?
  3. Auron

    Auron Well-Known Member

    Yes sorry, 2005 F4i with stock wheels, 180 on the rear. Been using Q3+ tires, people sometimes see the 120/60 and ask me what I'm thinking. I just like the way it turns better and don't have any bump absorption issues
  4. TurboBlew

    TurboBlew Registers Abusers

    Tell them you are thinking you like the way the lower aspect ratio tire feels? lol. Ever compared the 2 tire profiles side by side?
  5. Suzuka_joe

    Suzuka_joe Well-Known Member

    if you're on the edge of a 120/60 why not get the extra rubber on a 120/70. the taller tire should turn in quicker and provide a larger contact patch.
  6. Pneumatico Delle Vittorie

    Pneumatico Delle Vittorie Retired "Tire" Guy

    The OE sizes are 120/70 and 180/55 on your bike. The 120/60R17 is a very triangular size and not used much if not all for OE applications in the last 15 years. Because of this the 120/60 size will be limited in available high performance/race tires. So as you progress riding track days your options with this size will disappear.

    I would suggest you first check your current ride height and write down what you find. Then get off the 120/60 and switch to the 120/70 size ASAP. Then how fresh is your suspension and what condition is it in? So mount up a new set of 120/70 and 180/55 or maybe 180/60 and then check your suspension settings numbers and ride heights. Then go ride the bike with the new tires. You will probably find that with a 120/70 and a 180/55 the bike is a little slow with turn in? If so drop the front end (raise the forks in the triples) 5mm and go ride the thing. I would think you will feel better than what you had with the 120/60 front.

    Remember the suspension MUST be in good condition or your efforts will be masked by BS. And if you don't know your settings you are just spinning your wheels. Then if not happy get with a suspension person!
    ducnut and TurboBlew like this.
  7. Suzuka_joe

    Suzuka_joe Well-Known Member

    Or put a 180/60 on the back and a 120/70 in front and go ride it.
  8. Pneumatico Delle Vittorie

    Pneumatico Delle Vittorie Retired "Tire" Guy

    Yeah that works too but he needs to find a baseline and understand where the bike is from a set up standpoint first. And I'm not a fan of a 180/55 since we know how bad ass good a 180/60 is. A 180/55 is so 1995.
    ducnut likes this.
  9. RM Racing

    RM Racing Tool user

    If you like the 120/60, use it. Don’t overthink it.
  10. Tyson10R

    Tyson10R Member

    Getting to the very edge of a front tire means you're that much closer to lowsiding. Better to have a little extra room.
  11. Wheeliest

    Wheeliest ʍɥǝǝןıǝsʇ

    With decent geometry(stock or slightly lifted rear), you'll run through the back tire before the front on a 120/70 @ a trackdayer pace.

Share This Page